The National Intelligence Agency provides a great boost for your espionage activities, by promoting all existing spies and granting an additional spy. This is more useful to some nations than others, but is especially useful to those striving for a diplomatic victory. Unfortunately, this Wonder is available quite late in the game, so you will need to build lots of Constabularies and Police Stations. Try to set out and build them early, then halt your expansion until you finish the wonder - remember, every new city you found must also have the required building!

A National Intelligence Agency provides government resources for the acquisition of information and intelligence data key to providing security and national defense. Everything from covert operations, including espionage and infiltration, to the assessment of national security risks and response recommendations are made by these agencies. The Central Intelligence Agency of the United States is perhaps the most famous (or notorious) of the world's intelligence agencies, as the program has continually influenced global affairs through various means for decades.